_Did[elphys]. mesamericana_ Oken, Lehrbuch d. Naturgesch.,
pt. 3, 2:1152, 1816, type from northern MA(C)xico.
_Didelphis mesamericana_, Allen, Bull. Amer. Mus. Nat. Hist.,
16:256, August 18, 1902.
_Range._--Statewide.
_Specimens examined_, 7: nos. 100063-100067, 100074, 51396,
distributed by localities as follows: PAitzcuaro (3 mi. N, 6,700 ft.,
1; 2 mi. W, 6,700 ft., 2; 5 mi. S, 7,800 ft., 1), 4; TancA-taro, 1;
1-3/4 mi. S TacAimbaro, 5,700 ft., 1; 1 mi. E and 6 mi. S TacAimbaro, 1.
_Remarks._--The coarse overhair is white all the way to the base in
three specimens but is black in its distal two thirds (white in basal
third) in four specimens. The overhair, six centimeters anterior to
the base of the tail, is 83 (80-85) mm. long in the three gray
specimens (those with white overhair) and 68 (64-72) mm. long in the
black specimens. The ears and all four feet are black. The tail is
black in its proximal half and white in its distal half except in one
specimen in which the distal half is almost as dark as the proximal
half. Of the two largest specimens, one is a female from 1-3/4 mi. S
TacAimbaro and the other, a male is from 6 mi. S of the same place.
Measurements are: Total length, [M] 810, [F] 786; length of tail, [M]
360, [F] 348; length of hind foot, --, 58; condylobasal length, 110.0;
99.6; zygomatic breadth, 68.5; 59.6; length of nasals, 59.7, 45.0. The
tail amounts to 48, 48 and 47 per cent of the total length in
specimens from PAitzcuaro; 50 per cent in one from TancA-taro; 45 and 44
per cent in two from TacAimbaro. The subspecies _mesamericana_ probably
intergrades with _Didelphis virginiana virginiana_ by way of _D. m.
texensis_ and _D. v. pigra_, as Davis (1944:375) and other writers
suggest, in which case the proper name of the subspecies
_mesamericana_ would be _Didelphis virginiana mesamericana_. Until
intergradation is actually demonstrated, it seems best to use the name
_D. m. mesamericana_.
Most of our specimens were caught in steel traps, at meat baits, set
for small carnivores.
=Marmosa canescens canescens= (Allen)